I have an 88' GTU, and whenever I'm driving on the highway going like 65 - 80 mph, and there's a rattling sound coming from the dashboard. There's also a vibration in the steering wheel when going roughly the same speed. Anybody know what causes this and has anyone else had similar problems?

 

wheels off balance, or a dead tie-rod end

 

Thanks, I had one tie rod end replaced because it wouldnt pass inspection. I'll check the wheel balance too.